Note relatively short expected life-span for these bulbs
Here’s a quick summary. Hope it helps for others who are considering if these lights are worth the extra money and the shortened life time.
Do these lights offer brighter and wider illuminated field of view at night when compared to OEM / basic lights?
Do these lights offer whiter light when compared to OEM / basic lights?
Without a doubt!
Do these lights offer whiter light as white as HDL lights?
Not even close!
Do these lights worth the extra money and shortened life time?
If you want HDL performance - No.
If you want better performance lights compared to OEM / basic lights - Depends.
Sylvania basic is ~ $15 / pair; Sylvania Silverstar Ultra is ~ $32 / pair.
Silvania is rated at 500 hours (conservatively); Sylvania Silverstar Ultra is rated at 125 hours.
Basically, the question comes down to are you willing to pay 8x (2x the price, 1/4 the life time) the price for better performance lights, based on your driving needs?